In 2008, three smaller states flipped to the Democratic Party, although the race had been all but decided by the time that was discovered on Election Night.  Four years later, though, the same three states look a lot less friendly to Barack Obama in the latest NBC/Marist polls.  Colorado, Nevada, and Iowa all find themselves locked in a dead heat with the incumbent well below 50% in each, according to National Journal’s recap:

Mitt Romney is tied with President Obama in three key battleground states that Obama flipped from red to blue four years ago, according to new NBC News/Marist polls released early Thursday.

The states — Colorado, Iowa and Nevada — are relatively small, but each is an important and symbolic bellwether. In each state, voters overwhelmingly say the economy will be the most important issue in this year’s election, but Obama either trails Romney on this issue or, at best, ties him. …

• Obama holds only a one-point lead in Colorado, 46 percent to 45 percent, with 8 percent undecided. That is well within the poll’s margin of error of plus-or-minus 3 percentage points. Obama defeated Sen. John McCain, R-Ariz., in the state by nearly 9 points in 2008.
• The two candidates run even in [Iowa}, tied at 44 percent apiece. Two percent support another candidate, and 10 percent of voters are undecided. Each candidate holds between 80 percent and 85 percent of the vote among their respective party, while Obama leads Romney among independents by just 4 percentage points, within the margin of error.
• Obama won Nevada by double-digits in 2008, but today he leads Romney by just 2 points in the Silver State, 48 percent to 46 percent, the poll shows. Six percent of voters prefer another candidate or are undecided.

The curious thing about these polls is that Obama has significant leads among independents in all three states.  In Colorado, it’s 48/38, in Iowa 42/38 (close to a virtual tie), and 50/39 in Nevada.   Conventional wisdom in this election will be that independents will drive the election results, and that’s not the case in these surveys, although that might be because Marist included leaners in candidate support.

Enthusiasm could be another factor, but again, the results are mixed.  Romney supporters are slightly more likely to actually cast a vote in Colorado and Iowa (46/45 in both), and even up at 47% in Nevada.  In all three states, though, Obama has a better intensity of support among the already-decided.  When asked about intensity of interest in the election, Republicans and Democrats are virtually tied in Colorado for highest intensity (64% and 61% respectively), but Republicans have a bigger edge in Nevada (69%, 60%) and even more so in Iowa (62%, 50%).  It looks even better when cast as a value on the likelihood of voting, which Republicans win 87/79 in Colorado, 79/75 in Iowa, and 84/75 in Nevada.

Marist provides this analysis on enthusiasm in its reports, and the news isn’t good for Obama:

• Colorado – “A majority of Romney’s supporters — 52% — are very enthusiastic about casting their ballot in the fall while 41% of Obama’s supporters have a similar level of enthusiasm.”
• Iowa – “46% of Romney’s supporters are very enthusiastic about going to the polls in November. This compares with 38% of Obama’s backers who have a similar degree of enthusiasm.”
• Nevada – “53% of voters who support the president are very enthusiastic about going to the polls in the fall while a similar 51% of Romney backers say the same.”

Romney, of course, just clinched the nomination and is expected to increase enthusiasm among his supporters over the summer.  Obama has been President for almost three and a half years, and his campaign has been active for over a year.  Enthusiasm for Obama as a candidate won’t grow nearly as much.  Romney has all the upside here, and he’s already significantly ahead in two of the three states.

Assuming that these figures accurately reflect the status of the race in these three states, the big lessons are that Romney needs to connect more with independents in the three swing states while continuing to unite and excite the base — not an easy task.  Obama’s base is as fired up as it’s going to get in terms of supporting him personally, but he has to get them out to vote, which they seem significantly less interested in doing.  Overall, Obama’s showing significant weakness in all three states.  These may not be needed to win the election, but if it turns out close in the East, losing these states may be the straw that broke the camel’s back for Obama.

Update: I should have noted this earlier, but Marist doesn’t supply the D/R/I of the samples in these statewide polls, or at least they haven’t been supplying that data lately.