Presidential candidate and U.S. Sen. Bernie Sanders spoke Sunday to a crowd of close to 2,000 at a campaign rally in downtown Louisville, and the target of his criticism was a fellow senator – Majority Leader Mitch McConnell.

Sanders, fighting to be the Democratic nominee in 2020, accused McConnell of blocking important legislation in the U.S. Senate at the behest of corporate interests and detriment of the working class.

"I say to Mitch McConnell: Please stand with the working people in Kentucky and America, not your wealthy campaign contributors," Sanders said.

Sanders told the crowd that McConnell was obstructing legislation recently passed by the U.S. House that would raise the federal minimum wage to $15, expand background checks on gun purchases and strengthen the country's election security from foreign attacks.

McConnell has the right to vote against those bills and explain such opposition to his constituents, but he lacks the right to "stop democracy in the United States Senate," the Vermont senator said.

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"You don’t have the right to prevent debate and votes on the most important issues facing the working people of this country," Sanders said. "Stop your cowardice, have the guts to debate the issues."

Citing the fact that 10 of the country's poorest 25 counties are in Kentucky, Sanders claimed that McConnell had turned his back on the working class in his state and instead serves the interests of campaign contributors on Wall Street.

He urged the crowd to "follow the money" in order to understand his motives.

Kevin Golden, spokesman for McConnell's reelection campaign, reacted to the rally by issuing a statement tying Democratic Senate candidate Amy McGrath to Sanders.

"This won't be the last Democrat presidential candidate to come and do McGrath's dirty work but it's certainly is a questionable move to have the champion of socialism and the Green New Deal come to Kentucky and stump for her."

In his speech, Sanders touted his campaign's version of the "Green New Deal" – a $16.3 trillion plan unveiled on Thursday that aims to end fossil fuels use in the United States by 2050 and create 20 million new jobs in the new energy sector.

Sanders' plan states that it would be partly funded by new taxes and fees on the fossil fuels industry, while also providing displaced workers in the coal industry with a guaranteed salary for five years. It also calls for housing assistance, job training, health care, pension support and priority job placement.

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Sanders did not shy away from discussing coal miners in his speech, offering support for the former Blackjewel miners protesting in Harlan County and criticizing coal company CEOs for cheating workers out of pensions and benefits.

"Coal miners are not my enemy. Workers in the fossil fuel industry are not my enemies," Sanders said. "Climate change is our enemy."

Calling it a "moral responsibility" to aggressively confront man-made climate change, Sanders also said the country has a responsibility to look after and rebuild those rural communities that provided it power for generations.

The Republican Party of Kentucky issued a statement last week after Sanders' rally was announced, attempting to tie Sanders' proposal to phase out fossil fuels with the Democratic nominees in the races for governor and attorney general this fall: Attorney General Andy Beshear and Greg Stumbo.

“The extremist, job-killing policies of Bernie Sanders, Hillary Clinton, Andy Beshear and Greg Stumbo are wrong for Kentucky," GOP spokesman Mike Lonergan said.

Gov. Matt Bevin also released a video Sunday attempting to link Beshear and "crazy Bernie," saying "they share the same party, the same ideology, they share the same values on many fronts."

Hours before the rally, Sanders made an impromptu visit and speech a few blocks away to AT&T workers who began a strike against the company on Saturday. They allege AT&T was engaging in unfair labor practices during their new contract negotiations.

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Using a bullhorn as he spoke to about 100 striking workers from the back of a pickup truck, Sanders said they were "standing up against the kind of greed that is destroying this country.”

"To AT&T: Sit down at the negotiating table, bargain a fair and decent contract for your employees," Sanders said.

Roughly 20,000 union members of the Communications Workers of America in the southeast launched the strike against AT&T on Saturday, including 2,500 workers in Kentucky and nearly 1,000 in Louisville.

Reach reporter Joe Sonka at jsonka@courierjournal.com or 502-582-4472 and follow him on Twitter at @joesonka. Support strong local journalism by subscribing today: courierjournal.com/subscribe.