Kansas Sen. Pat Roberts with his wife, Franki, acknowledges the crowd after winning re-election over independent candidate Greg Orman, Tuesday night, Nov. 4, 2014, at a Kansas Republican gathering at the Capitol Plaza Hotel.

Topeka ? U.S. Sen. Pat Roberts fended off a tough re-election challenge Tuesday from suburban Kansas City businessman Greg Orman, a major victory for Republicans in a Kansas race that helped the party secure a Senate majority.

Roberts’ victory capped the most hard-fought campaign of his 34-year career in the U.S. Senate and House, coming in what was one of the nation’s most unusual Senate contests because it lacked a Democratic opponent.

“The country was counting on us to help deliver a Republican majority to the Senate, and we delivered,” Roberts told a cheering crowd of supporters at a Republican election night party in Topeka.

Roberts, 78, narrowly survived a tea party challenge in an August GOP primary, then — as it seemed his re-election was all but assured — was thrown a political twist when Democratic nominee Chad Taylor dropped out in September, consolidating the opposition behind Orman. The Olathe businessman asserted Roberts was no longer representing the state well and had instead become a part of the partisan gridlock in Washington.

Orman, 45, told a subdued audience of supporters in Overland Park that he had called Roberts and congratulated him on his victory.

“While Sen. Roberts won tonight, we didn’t lose,” Orman said. “We not only ran against Sen. Roberts, we ran against the whole Washington establishment.”

Roberts had campaigned not so much by stressing his specific accomplishments but by telling voters in the traditionally Republican state that his re-election was essential to GOP efforts to wrest control of the chamber from Democrats and provide a legislative check on the policies of President Barack Obama.

That message seemed to appeal to some voters.

Sharon Miklos, 51, a massage therapist from Peck, said she voted for Pat Roberts, because “I don’t want to give Obama any more power.”

Others expressed unhappiness with both Roberts and Orman but cast their votes based either on party loyalty or a general desire for change.

Retired equipment salesmen Phillip Cohan said Roberts has been in Washington too long. “But he’s the only Republican running,” said Cohan, 68, of Overland Park. “So we don’t have much of a choice. “

Roberts said he learned a lot during what he acknowledged was tough campaign.

“It was a hard-fought election, and I’ve heard my marching orders loud and clear,” Roberts said. “I will be bold, I will be conservative and I will be constructive. And I promise you this, we will get things done.”

With Republicans newly in charge of the chamber, Roberts said he expects to become chairman of the Senate Agriculture Committee. He pledged in his election night speech to “be a champion for our farmers and ranchers,” as well as for U.S. military members.

A Marine veteran and former House Agriculture Committee chairman, Roberts never has gotten less than 60 percent of the vote in his three previous Senate campaigns. But he got just 48 percent of the vote this August while surviving a four-way GOP primary and got just a little over half the vote in the general election.

Preliminary findings from exit polls conducted for The Associated Press and television networks showed an age gap among voters. Orman was favored by a 2-to-1 margin among voters younger than 30 while Roberts performed particularly strong among those over age 65. Whereas Orman did well among self-described political moderates, Roberts drew support from those who believe the federal government should do less — a common campaign theme for Republicans.

The first signs that Roberts faced an unusually tough re-election appeared as a tea party-backed Republican candidate, Milton Wolf, questioned whether Roberts had grown out of touch with Kansas residents during his long tenure in Washington. Among other things, Wolf noted that Roberts owns a home in suburban Washington but lists a rented room in the Dodge City home of one of his supporters as his official Kansas residence.

During the general election campaign, Roberts tried to portray Orman as a liberal Democrat running under the guise of an independent. Orman ran briefly as a Democrat against Roberts in 2007 before dropping out of that race. Orman contributed to the 2008 Democratic presidential campaigns of Obama and Hillary Rodham Clinton, but he has also given money to Republicans, such as Scott Brown’s campaign for the U.S. Senate in Massachusetts in 2010.

Orman suggested Tuesday night that he might still have a political future, though he mentioned no specific future races.

“My firm hope and belief is also that we send a message to other aspiring independents out there that this can be done,” he said.