National pollsters have already released surveys showing Rick Santorum taking a lead over Mitt Romney in Romney’s native state of Michigan.  Today, three state-based polls concur, showing leads from just under four points to ten points in the key battleground state.  The Detroit News poll shows the tightest margin (via Politico’s Morning Blast e-mail):

Former Pennsylvania Sen. Rick Santorum has a slim lead over Mitt Romney, an indication the Michigan native son has yet to convince state voters he should be the Republican nominee for president, a Detroit News poll shows.

Santorum leads Romney 34 percent to 30.4 percent among likely Republican primary voters, but the gap is within the margin of error of 4.4 percentage points.

Former House Speaker Newt Gingrich had support from 11.6 percent of respondents, former U.S. Rep. Ron Paul had 8.9 percent and 12.4 percent was undecided.

USA Today reports on the other two polls, which show leads of nine and ten points:

The MRG Michigan Poll shows Santorum, a former U.S.senator from Pennsylvania, with 43% of the support to 33% for native son Mitt Romney, who has long been considered the front-runner in Michigan.

In the MRG poll, former House speaker Newt Gingrichcame in at 11% and Rep. Ron Paul of Texas had 8%. …

Mitchell Research, a polling firm in East Lansing, Mich., also has a new survey out showing Santorum with a 9-point lead over Romney in the Feb. 28 presidential primary in Michigan.

The Mitchell poll was done for MIRS, the Michigan Information & Research Service, and shows Santorum at 34% to Romney’s 25%. Less than two weeks ago, Romney was at 31%, with a 15-point lead over former Gingrich (16%), trailed by Santorum (15%) and Paul (15%).

In the new poll, which has a margin of error of plus or minus 4.6-percentage points, Paul trails Santorum and Romney with 11% and Gingrich is behind them with 5% of the survey respondents.

The MRG poll was conducted among 800 Republican voters, which might be problematic if USA Today means registered Republicans only.  Independents can vote in the GOP primary in Michigan, and the wording implies that the poll was conducted among registered rather than likely Republicans without any independents.  The Mitchell poll, however, surveyed 455 likely voters in the primary, which is a better sample — and one that came up with essentially same result.   The Detroit News poll surveyed 500 likely voters, similar to the Mitchell poll, but with somewhat more divergent results.

Clearly, Santorum has momentum in Michigan, and as Tina noted yesterday, in Arizona too, although he still trails in the latter.  One question that arises is that of timing.  Both of these contests are still almost two weeks away, which is plenty of time for Romney to spend a lot of cash to slow Santorumentum down, and possibly reverse it.   The danger for Santorum is peaking too soon and raising expectations in Michigan before the Super Tuesday contests.  If Santorum ends up losing Michigan after getting leads across the board in all these polls, it will be difficult to regenerate momentum in a single week to take on Romney in ten states.

Santorum’s fundraising has picked up and he’s trying an attack strategy on Romney designed to undercut Romney’s credibility by painting him as a mudslinger, but the effectiveness of that strategy has yet to be tested.  The four candidates return for another debate on February 22nd, and Santorum can expect the hot-seat treatment from Romney and perhaps Gingrich as well, a new role for Santorum in these debates. Romney has already gone after Santorum as a big-government, big-spending Washington insider, but the Weekly Standard defends Santorum on those charges:

The National Taxpayers Union (NTU) has been rating members of Congress for 20 years.  NTU is an independent, non-partisan organization that — per its mission statement — “mobilizes elected officials and the general public on behalf of tax relief and reform, lower and less wasteful spending, individual liberty, and free enterprise.”  Steve Forbes serves on its board of directors.

For each session of Congress, NTU scores each member on an A-to-F scale.  NTU weights members’ votes based on those votes’ perceived effect on both the immediate and future size of the federal budget.  Those who get A’s are among “the strongest supporters of responsible tax and spending policies”; they receive NTU’s “Taxpayers’ Friend Award.”  B’s are “good” scores, C’s are “minimally acceptable” scores, D’s are “poor” scores, and F’s earn their recipients membership in the “Big Spender” category.  There is no grade inflation whatsoever, as we shall see.

NTU’s scoring paints a radically different picture of Santorum’s 12-year tenure in the Senate (1995 through 2006) than one would glean from the rhetoric of the Romney campaign.  Fifty senators served throughout Santorum’s two terms:  25 Republicans, 24 Democrats, and 1 Republican/Independent.  On a 4-point scale (awarding 4 for an A, 3.3 for a B+, 3 for a B, 2.7 for a B-, etc.), those 50 senators’ collective grade point average (GPA) across the 12 years was 1.69 — which amounts to a C-.  Meanwhile, Santorum’s GPA was 3.66 — or an A-.  Santorum’s GPA placed him in the top 10 percent of senators, as he ranked 5th out of 50.

Across the 12 years in question, only 6 of the 50 senators got A’s in more than half the years.  Santorum was one of them.  He was also one of only 7 senators who never got less than a B.  (Jim Talent served only during Santorum’s final four years, but he always got less than a B, earning a B- every year and a GPA of 2.7.)  Moreover, while much of the Republican party lost its fiscal footing after George W. Bush took office — although it would be erroneous to say that the Republicans were nearly as profligate as the Democrats — Santorum was the only senator who got A’s in every year of Bush’s first term.  None of the other 49 senators could match Santorum’s 4.0 GPA over that span.

I’ve been seeing a lot of comments and tweets about Santorum’s supposed profligacy as Senator, but that doesn’t match his record vis-a-vis the NTU scoring.  People have honest differences with Santorum on the emphasis of social issues (although Santorum himself has emphasized his economic plans in this campaign), and I wrote that I have a few disagreements with Santorum’s positions, DADT among them.  He’s not a perfect conservative, to be sure, and questions about how he would stack up against Barack Obama in the general election are legitimate concerns.  However, the alternatives are the person who signed an individual health-care mandate into law in Massachusetts, and the man who both backed individual mandates until 2010 and sat on a couch with Nancy Pelosi to push global-warming alarmism a few years before that, and both of whom also spent three or four weeks sounding more like an Occupier on Bain Capital and Freddie Mac work than a Republican.  Those issues occurred  more recently than any sins committed by Santorum while in the Senate, which is why I’m not buying the idea that Santorum is the big-government candidate about which I should be worried.