A former Manhattan mayor little known to rural western Kansas voters is giving Congressman Tim Huelskamp an aggressive re-election challenge.

Democrat Jim Sherow has mounted a hard-fought challenge in the sprawling 1st District of Kansas despite seemingly overwhelming odds in a heavily Republican district against a well-funded incumbent. Sherow has crisscrossed the mostly rural district on bus tours to meet voters, stretching his already limited budget.

It remains unclear whether Huelskamp is vulnerable, largely because there is no reliable independent polling on the race.

While many statewide races are close, it is difficult for a Democrat to win in the 1st District, where 53 percent of registered voters are Republicans. By contrast, the number for registered Republican voters statewide is 44 percent.