A defiant Rand Paul is brushing off weak fundraising and weaker poll numbers as would-be donors and home state Republicans push him to abandon an uphill presidential bid to focus on his Senate re-election.

While showing some frustration, the first-term Kentucky senator this week claimed his superior political organization would prove wrong those doubting his chances in the White House contest. At the same time, he released fundraising numbers that place him squarely in the bottom tier of the GOP’s 2016 class over the last three months, a painful symbol of stalled momentum for the libertarian favorite who was considered a major presidential contender earlier in the year.