Vermont Sen. Bernie Sanders addressed more than 11,000 people in the biggest rally of his campaign in Phoenix on Saturday, building on the growing tide of enthusiasm for his campaign.

The Democratic candidate for president spoke for nearly an hour, focusing on the central themes of his campaign, including income inequality, money in politics, and growing wages.

“For the last 40 years the great middle class of this country—once the envy of the world—has been disappearing,” Sanders said. ”

‘We need to stand together to make a political revolution where we create an America that works for all of us,” he continued. “Enough is enough—the billionaires are not going to have it, it’s our country. Let’s create that nation!”

Citing figures from the Phoenix Convention Center, Sanders’ campaign spokesman said 11,347 people attended the rally.

Though he remains 40 percentage points behind Democratic frontrunner Hillary Clinton in the Real Clear Politics average of polls, Sanders has seen a surge in interest among liberals in the Democratic base with a message of economic populism and a defiant tone.

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