Bernstein analysts have identified Circle and Coinbase as prime investment opportunities in the stablecoin sector, citing their partnership in USDC as a significant factor. The analysts note that while AI-driven payments could boost stablecoin demand, this is currently limited, with Coinbase's x402 protocol processing $25 million in the past month and Stripe's machine payment protocol handling $5,000 in its first week. The investment thesis for stablecoins is bolstered by their expanding mainstream applications, including cross-border payments and remittances. USDC has achieved record supply and transaction volumes, leading the market in transaction volume share.