In October 2013, Sasse announced his candidacy for the United States Senate seat occupied by Republican Mike Johanns, who was not running for reelection.
As of October 2013, his fundraising total of nearly $815,000 from individual donors in his first quarter broke Nebraska's previous record of $526,000 from individual donors, set in 2007 by Johanns while he was the U.S. Secretary of Agriculture.

Upon announcing his candidacy, Sasse expressed strong opposition to the Affordable Care Act.
His primary opponent, Shane Osborn, questioned the depth of Sasse's opposition to the ACA, publicizing articles and speeches Sasse delivered during and after the act's passage through Congress; according to the Omaha World-Herald, "Osborn's campaign appears intent on questioning whether Sasse is a true conservative."
The Osborn campaign cited, among other pieces, a 2009 Bloomberg Businessweek column titled "Health-Care Reform: The Rush to Pass a Bad Bill", stating that "There's an emerging consensus that this [an individual mandate] might be a good idea", and a 2010 speech in which Sasse said Republicans would probably lack the votes to repeal the ACA, stating that "a middle-class entitlement has never been repealed", and opining that Republicans had failed to offer a viable alternative, preferring to stage "symbolic repeal votes".
Sasse's response to the Osborn campaign's assertions was that in his articles and speeches, he was describing the political landscape rather than giving his own opinions on the merits of the ACA's provisions; to a World-Herald reporter, he declared, "I have never changed my position on thinking Obamacare is a bad idea".

On May 13, 2014, Sasse won 92 of 93 counties and secured the Republican nomination with 109,829 votes, or 49.4% of all votes cast; banker Sid Dinsdale came in second, with 49,829 votes (22.4%), followed by Osborn, with 46,850 votes (21.1%).

On November 4, 2014, Sasse won the general election for the U.S. Senate, defeating Democratic nominee David Domina with 64.4% of the vote to Domina's 31.5%.
In October 2013, Sasse announced his candidacy for the United States Senate seat occupied by Republican Mike Johanns, who was not running for reelection. As of October 2013, his fundraising total of nearly $815,000 from individual donors in his first quarter broke Nebraska's previous record of $526,000 from individual donors, set in 2007 by Johanns while he was the U.S. Secretary of Agriculture.
Upon announcing his candidacy, Sasse expressed strong opposition to the Affordable Care Act. His primary opponent, Shane Osborn, questioned the depth of Sasse's opposition to the ACA, publicizing articles and speeches Sasse delivered during and after the act's passage through Congress; according to the Omaha World-Herald, "Osborn's campaign appears intent on questioning whether Sasse is a true conservative." The Osborn campaign cited, among other pieces, a 2009 Bloomberg Businessweek column titled "Health-Care Reform: The Rush to Pass a Bad Bill", stating that "There's an emerging consensus that this [an individual mandate] might be a good idea", and a 2010 speech in which Sasse said Republicans would probably lack the votes to repeal the ACA, stating that "a middle-class entitlement has never been repealed", and opining that Republicans had failed to offer a viable alternative, preferring to stage "symbolic repeal votes". Sasse's response to the Osborn campaign's assertions was that in his articles and speeches, he was describing the political landscape rather than giving his own opinions on the merits of the ACA's provisions; to a World-Herald reporter, he declared, "I have never changed my position on thinking Obamacare is a bad idea".
On May 13, 2014, Sasse won 92 of 93 counties and secured the Republican nomination with 109,829 votes, or 49.4% of all votes cast; banker Sid Dinsdale came in second, with 49,829 votes (22.4%), followed by Osborn, with 46,850 votes (21.1%).
On November 4, 2014, Sasse won the general election for the U.S. Senate, defeating Democratic nominee David Domina with 64.4% of the vote to Domina's 31.5%.
Ben Sasse