WASHINGTON (AP) — Democrats secured a majority in the Senate on Tuesday, snatching Republican-held seats in Massachusetts and Indiana and turning back fierce, expensive challenges in Virginia, Ohio, Wisconsin and Connecticut to maintain the control they’ve held since 2007.

With a third of the Senate up for election, Republicans were undone by candidate stumbles. GOP hopefuls in Missouri and Indiana uttered clumsy statements about rape and abortion that severely damaged their chances and the party’s hopes of taking over. The losses of Senate seats in Massachusetts and Indiana, combined with independent Angus King’s victory in the Republican-held Maine seat, put the GOP too far down in their already uphill climb.

Democrats held open seats in Virginia, Wisconsin and New Mexico, and were leading in North Dakota shortly after midnight. The only pickup for the Republicans was Nebraska, where Deb Fischer denied former Democratic Sen. Bob Kerrey’s bid to return to the Capitol.

Democrats, once on the wrong side of the political math with 23 seats at risk compared with only 10 for the GOP, suddenly looked like they could increase their numbers. They entered the night with a 53-47 edge, including two independents who caucus with them. After midnight, Democrats controlled 52 seats to the GOP’s 44 with three races still outstanding and one newly elected independent, Angus King of Maine, saying he hasn’t decided which party he will align with.

In charge again, Senate Majority Leader Harry Reid, D-Nev., said Republicans brought defeat on themselves with their preoccupation with denying President Barack Obama a second term.

“Things like this are what happens when your No. 1 goal is to defeat the president and not work to get legislation passed,” Reid said. “The strategy of obstruction, gridlock and delay was soundly rejected by the American people. Now they are looking to us for solutions,” he said in a separate statement.

The results were a bitter loss for the GOP and are certain to prompt questions about the promise and peril of the tea party movement that just two years ago delivered a takeover of the House to the GOP. In 2010, three tea party Senate candidates in Nevada, Delaware and Colorado cost Republicans seats they were favored to win. On Tuesday, a tea party-backed candidate in Indiana denied the GOP a seat that the party had been favored to win, while Fischer and tea party-backed Ted Cruz of Texas prevailed in their races.

Democratic Rep. Joe Donnelly edged out tea party-backed Indiana state treasurer Richard Mourdock in a race rocked by the Republican candidate’s awkward remark that pregnancy resulting from rape is “something God intended.”

Mourdock also upset some Indiana voters for his decision to sue to stop the federal auto bailout of Chrysler, which means jobs building transmissions to thousands in Kokomo. And he alienated some in his own party with his divisive win over six-term Sen. Richard Lugar in the May GOP primary. Lugar refused to campaign for him.

In Massachusetts, Democrat Elizabeth Warren knocked out Republican Sen. Scott Brown, who had stunned the political world in January 2010 when he won the late Sen. Edward M. Kennedy’s seat. The strong Democratic tilt in the state and President Barack Obama’s easy win over former Gov. Mitt Romney helped the consumer advocate in her bid.

The Massachusetts race was one of the most expensive in the country — $68 million — even though both candidates agreed to bar outside spending.

In Missouri, Democratic Sen. Claire McCaskill was considered the most vulnerable incumbent, but Republican Rep. Todd Akin severely damaged his candidacy in August when he said women’s bodies have ways of avoiding pregnancy in instances of “legitimate rape.” GOP leaders, including Romney, called on him to abandon the race. Akin stayed in.

The results ensure plenty of new faces in the Senate, many of them familiar from the House. Republican Rep. Jeff Flake won in Arizona and will join Democratic Reps. Mazie Hirono of Hawaii and Martin Heinrich of New Mexico. In Wisconsin, Democratic Rep. Tammy Baldwin defeated former four-term Gov. Tommy Thompson and will be the first openly gay senator. .

The caustic campaign for control of the Senate in a divided Congress was marked by endless negative ads and more than $1 billion in spending by outside groups on races from Virginia and Florida to Montana and New Mexico. The outcome in Ohio and Virginia was closely linked to the presidential race.