Bagley is a major political donor and fundraiser who "over the years [has] raised millions of dollars for Democratic candidates." Her late husband, Smith W. Bagley (1935–2010), was an heir to the R. J. Reynolds tobacco fortune and a Finance Chair for the Democratic National Committee, and the Bagleys were regarded as "two of the heaviest financial hitters in the [Democratic] party." Closely associated with the Clintons since Bill Clinton’s 1992 presidential campaign, She was a major fundraiser during Hillary Clinton’s presidential campaigns in 2008 and 2016. Additionally, she and her husband have contributed over $1,000,000 to the Clinton Foundation. She was also "part of the national finance team for the Obama campaign, having personally raised over $350,000" as of August 2008. Bagley also "raised the maximum $600,000 for President Obama's inauguration events" in 2009. President Obama visited her residence in the Georgetown neighborhood of Washington D.C. in 2011.