Cory Gardner

These are the 13 races that will determine control of the Senate in the next Congress. To win control, Democrats would need to net-gain four seats, or three seats plus control of the White House.

Five Republican Senate incumbents are looking increasingly vulnerable, while fundraising reports provide glimpses of Democratic strength.

While former Colorado Gov. John Hickenlooper is still seen as having an edge in his state's Senate primary, recent and past comments about race have dampened enthusiasm for him among some voters.

Some of the biggest players in Colorado's marijuana industry may influence 2020's high profile U.S. Senate race.

Colorado Sen. Cory Gardner has to be more careful than most Republicans talking about impeachment, as he's seeking reelection in a very purple state. GOP voters are split on Gardner's position.

Hickenlooper painted himself as a relative centrist in the crowded, progressive presidential field. But he wasn't able to gain much traction. O'Rourke plans to focus on the president.

Vice President Pence did not criticize the president's about-face on who is to blame for violence in Charlottesville. Some GOP leaders have spoken up, but not all derided the president specifically.

President Obama's decision to send special operations ground forces into Syria is again prompting calls for specific authorization from Congress to wage war.