WASHINGTON (REUTERS) - Republicans appeared poised to retain control of the US Senate on Wednesday (Nov 4), after Senator Susan Collins defied political odds to win re-election in Maine and other Republican incumbents led Democrats in a handful of undecided races.
Democrats, who had been favoured to win the Senate majority heading into Tuesday's election, had a net gain of only one seat to show by Wednesday afternoon as their options for further increases dwindled, despite a huge Democratic money advantage going into the final weeks of the campaign.
Republicans currently hold a 53-47 seat Senate majority. To win control, Democrats would need to net three Republican-held seats if Democrat Joe Biden wins the White House and Senator Kamala Harris becomes vice-president with the tie-breaking Senate vote. If Biden loses to Republican President Donald Trump, Democrats would need four seats.
Of five Senate races still undecided, Republican incumbents led in Alaska, Georgia and North Carolina, while Democratic Senator Gary Peters led Republican John James by a slight margin in Michigan.
A second Senate contest in Georgia was headed for a Jan 5 runoff between Republican Senator Kelly Loeffler and Democratic challenger Raphael Warnock.
The best news for Republicans came from Maine where Collins, a 67-year-old Republican moderate once seen as imperiled, pulled off a surprise victory over Democrat Sara Gideon, 48, speaker of the Maine State House of Representatives.
"I feel that this is an affirmation of the work that I'm doing in Washington to fight hard every day for the people of Maine," Collins told reporters.
Democrats ousted Republican Senators Martha McSally of Arizona and Cory Gardner of Colorado. But those victories were cut to a net gain of one by Democratic Senator Doug Jones's loss in Alabama.
The Democrats' path to victory narrowed further as Republican incumbents Joni Ernst of Iowa, Steve Daines of Montana, John Cornyn of Texas and Lindsey Graham of South Carolina - all once viewed as vulnerable to ouster - fended off Democratic challengers to win re-election.
Republicans also held onto an open seat in Kansas, where Republican Roger Marshall defeated Democrat Barbara Bollier.
A Republican-run Senate would pose deep problems for Biden if he wins the presidency, likely blocking huge parts of his legislative agenda, including expanding healthcare and fighting climate change. A second Trump term would face a similar hurdle in the House of Representatives, where Democrats held onto a slimmed-down majority.
The Senate race in Michigan drew criticism from Trump just before the contest flipped in the Democrat's favour.
"Wow! It looks like Michigan has now found the ballots necessary to keep a wonderful young man, John James, out of the U.S. Senate. What a terrible thing is happening!" Trump wrote on Twitter.
In North Carolina, Republican Senator Thom Tillis declared victory over his Democratic challenger, Cal Cunningham. But the race had not been called, with Tillis leading by less than 2 percentage points.
Republican Senator David Perdue was more than 3 percentage points ahead of Democrat Jon Ossoff in Georgia. In Alaska, Republican Senator Dan Sullivan held a sizable lead with half of the vote counted.
Gardner, a first-term Republican long seen as his party's most vulnerable Senate incumbent, lost to former Colorado Governor John Hickenlooper in a formerly Republican state where demographic changes have increasingly favoured Democrats in recent years.
Democrat Mark Kelly, a former US astronaut who had long dominated the Arizona race, defeated McSally by more than 5 percentage points in the onetime Republican stronghold.
Jones, the most vulnerable Democrat, lost as expected to challenger Tommy Tuberville in the Republican stronghold of Alabama.
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