(CNN) - John Hickenlooper, who has struggled to break through the crowded Democratic presidential field, spoke to Senate Minority Leader Chuck Schumer late last week about running for the Senate from Colorado, a race he has resisted joining but is keeping an open mind about, a top aide tells CNN.
"He is still in the race for president, but he hasn't closed the door to anything," said Peter Cunningham, the communications director for the former Colorado governor.
The latest conversation between Hickenlooper and Schumer took place in New York, following the CNN presidential debates in Detroit. The two have spoken repeatedly about the Senate contest, but Hickenlooper has been insistent on keeping his presidential campaign alive.
Yet Hickenlooper is also facing the reality of not making the next debate in September, according to people familiar with his campaign operation. He is well behind in the number of donors and level of polling needed to qualify, they said.
Hickenlooper, a former Denver mayor, is in Iowa this week, pressing ahead with his presidential campaign schedule. He has told friends that he believes he is what the party needs as a presidential nominee, but has also acknowledged that his message has failed to gain traction.
"He still believes he has an important contribution to make to the Democratic primary debate," Cunningham said.
But a decision is looming for Hickenlooper, aides said, considering candidates have until August 28 to qualify for the next round of debates. He is also running short on campaign funds and will be faced with deciding whether to invest his own money in the race or dropping out in the coming weeks.
A month ago, Hickenlooper shook up his presidential team, allowing his campaign manager, finance director and spokeswoman to leave.
Schumer, who has been struggling to recruit Democratic candidates in his uphill quest to win control of the Senate, is focusing his attention on Hickenlooper but giving him space to make his own decision. Schumer wants him to challenge Sen. Cory Gardner, who is among the potentially vulnerable Republicans in 2020.
Despite a crowded Democratic primary, Hickenlooper is seen as the party's strongest candidate to take on Gardner. Curtis Hubbard, a Democratic strategist for a firm that has worked for Hickenlooper in the past, has recently registered domain names like Hick4Senate.com in the hope that the former governor switches races.
An aide to Schumer referred questions to the Democratic Senatorial Campaign Committee, which did not immediately respond to a request for comment.