MENLO PARK, CA – Audi of America believes it has found the fourth leg to its model-lineup stool with its long-awaited all-new A3 small car, arriving at U.S. showrooms this spring.

It took Audi nearly a year after the debut of the A3 Sportback to chisel out a 4-door notchback for the U.S. market. But the launch comes just in time for the brand to go head-to-head with the new Mercedes CLA sedan and BMW 2-Series coupe, as the German marques kick the drive down market into second gear in an effort to capture a growing number of budget-minded buyers with a penchant for luxury-brand labels.

The new A3 sits on parent Volkswagen’s proliferating MQB platform, which underpins the reborn VW Golf that also arrives in the U.S. this year. Power comes from VW’s turbocharged EA888 4-cyl. engine family and includes the base 170-hp 1.8L and optional 220-hp 2.0L, both partial-zero-emissions certified and linked to Audi’s 6-speed dual-clutch automatic transmission.

The sedan, which replaces the outgoing A3 5-door, is the first in a string of seven A3 variants to come that will include a drop-top cabriolet, limited availability of the Sportback model and a performance S version, all due in the fourth quarter, plus the long-awaited Q3 CUV slated to make its U.S. debut in August or September.

In all, there will be five unique powertrains offered, including a plug-in electric hybrid, a 2.0L TDI diesel due in the fall and high-output version of the 2.0L TFSI gasoline engine, rated at 290 hp in Euro-spec form, for the performance S model.

The Sportback, which won’t join the lineup until 2015, will be offered initially only with the plug-in hybrid powertrain that mates a 1.4L turbocharged gasoline engine with a 75-kW (101-hp) electric motor, fueled by lithium-ion batteries. But Audi of America President Scott Keogh hints other engines may be offered with the U.S.-spec Sportback down the road.

For now the A3 hits the market as a sedan only, starting fairly well equipped at $29,900. Standard features include a 10-speaker sound system with HD Radio and a 90-day SiriusXM subscription, an SD-card slot with 32GB capacity, cruise control, rain-sensing wipers, automatic headlamps and Audi’s Pre-Sense basic package that detects when an emergency maneuver is being made and prepares the occupant-restraint systems for a possible collision. Stepping up to the 2.0L engine pushes the base price to $32,900.

Options include a navigation system with Audi’s MMI controller and touchpad handwriting system, a 705-watt Bang & Olufsen sound system with 14 speakers, keyless ignition and adaptive cruise control.

Also optional is Audi’s first 4G LTE data connection, provided in partnership with AT&T. The Wi-Fi hotspot can be had for $99 for a 6-month/5GB plan or $499 for a 30-month/30GB subscription.