With a little more than two weeks till Election Day, 33 Tea Party-backed candidates are in tossup races or running in House districts that are solidly or leaning Republican, and 8 stand a good or better chance of winning Senate seats.

While the numbers are relatively small, they could exert outsize influence, putting pressure on Republican leaders to carry out promises to significantly cut spending and taxes, to repeal health care legislation and financial regulations passed this year, and to phase out Social Security and Medicare in favor of personal savings accounts…

Polls suggest that in the Senate, the hurt may outweigh the help. The four seats that are leaning or solidly Republican and feature Tea Party candidates were in Republican hands to begin with. Ms. O’Donnell’s surprise upset of the establishment candidate in Delaware dashed Republican hopes for a seat that even Democrats had expected to lose. The Tea Party candidate in Nevada, Sharron Angle, has improved the odds that Senator Harry Reid, the leader of Democratic majority, hangs onto his seat. And having Rand Paul as their nominee has made the fight in Kentucky tougher than Republicans anticipated.